Nearly 60 million adults in the United States have high blood pressure (BP) in the pre-hypertension (SBP 120-139 or DBF 80-89). Hypertension is estimated to account for 1 in 8 deaths in the world, and in the US the direct and indirect costs of high BP are estimated to reach $59.7 billion in 2005. JNC-7 guidelines recommend lifestyle modifications for prehypertension, followed by antihypertensive medication if BP progresses to Stage I hypertension. Mindfulness-based Stress Reduction (MBSR) is an increasingly popular practice that has been purported to alleviate stress and treat certain health conditions. Some stress management therapies and one meditation therapy (e.g., Transcendental Meditation) have shown promise in reducing elevated BP, but MBSR has not been evaluated as a treatment for high BP. When added to lifestyle modification advice, MBSR may be an appropriate complementary treatment for prehypertension. However, prior to a large randomized clinical trial of MBSR for prehypertension and/or hypertension, pilot data is necessary to provide preliminary evidence of a treatment effect and to evaluate feasibility. This feasibility randomized clinical trial of MBSR for unmedicated prehypertension will provide preliminary evidence to support a larger randomized clinical trial by evaluating the feasibility and safety of MBSR as a complementary treatment for high BP and by documenting any treatment effect. Sixty patients with unmedicated BP in the range of SBP 120-139 mm Hg or DBP 80-89 mm Hg will be randomly assigned to MBSR or a progressive muscle relaxation control condition. All patients will receive lifestyle modification advice. Patients will complete 8 weeks of MBSR delivered in a group format by an experienced psychologist trained in MBSR or 8 weeks of progressive muscle relaxation training matched for therapist contact and homework. Patients BP will be assessed prior to randomization and following treatment by researchers blind to treatment assignment. Accrual rates, acceptance of randomization, treatment adherence, treatment fidelity, and patient satisfaction with treatment will be evaluated. [unreadable] [unreadable] [unreadable]